Sample rates for analog-to-digital converters (ADCs) and for digital-to-analog converters (DACs) continue to increase. Increasing sample rates, in turn, drive requirements for signal conversion components used within the data path of such converters, whether for purposes of analog-to-digital conversion or for digital-to-analog conversion. For example, referring to both ADCs and DACs, high end converters have emerged that are capable of operating in the range of approximately four giga-samples per second. Converters operating in the giga-sample range have been used in various technologies including, but not limited to, spectrum sensing equipment as used in cognitive radios and in advanced “full-spectrum” cable modem Edge Quadrature Amplitude Modulation (QAM) and Cable Modem Termination System (CMTS) equipment.
Signal processing circuits that process data from ADCs or that prepare data for output to DACs can have clock signals in the range of approximately hundreds of megahertz. This means that the difference in frequency between the clock signal used to drive the signal processing circuitry and the clock signal corresponding to circuitry processing the analog signals (e.g., ADCs and/or DACs) can be an entire order of magnitude or more.